2.5 td 19j reving up full rpm plenty of knocking

Hi there, wondering if anyone could help me with a few issues I have been having in my 90. The old girl has a few things wrong with her as you can imagine. The main problem is that it suddenly revs up randomly. Now I don't think it's runing on its own oil, taken the intake of and looked at the turbine and it seems fine no oil. Also once I turn of the ignition it settles down. It appears to happen when the engine is hot and anywhere between 1st and 3rd so far. Usually after it has happened ed there is a smell of diesel. Also a fair amount of white smoke but not always. I don't think there is diesel in the oil however it has been reading rather high. It's becoming rather worrying and happens usually once a trip. I would appreciate it greatly if anyone could shed some light on what's been happening.

hi I had same problem this turned out to be diaphragm mounted some where on injection pump I cant remberwhere letting diesel in to inlet manifold and ocasionly when engie was hot it would rev like mad and chuck out lots of black smok does the engine breather pipe go in to pipe between air filter and in let manifold if so if engine is breathing heavley it could be running on its own blow by fumes especily when hot

The breather pipe has a fair amount of oil on it could be the culprit however there appears to be very little in the air intake. Will look into the diaphragm problem I get white smoke which is worrying however no oil in the turbo